The mouse light response of intrinsically photosensitive retinal ganglion cells: A model for understanding the second messenger pathway

Modeling of light entrainment of the mammalian circadian clock requires input exclusively from the retina. This photo-response is unique and also expresses melanopsin, a novel vertebrate opsin, which is necessary for initiating the light response in these cells. Among all known vertebrate opsins, melanopsin is unique. These light sensitive ganglions cells were just discovered 10 years ago and the biochemistry underlying the light response remains to be definitively elucidated. The goal of our joint research project is to model the light dependent depolarization. The drawing depicts the crystallized molecular structure of melanopsin.